A group of scientists dressed in lab coats brought hard evidence to the march, and presented their findings on a giant rolling chalkboard.

“We have so much data from different angles,” said Lucky Tran, a molecular biologist. “It’s not just one graph, if you see our chalkboard, it’s multiple lines of evidence. It’s really the weight of the that evidence in total: carbon is going up, temperature is going up, glaciers are melting, ocean are acidifying. All of that is scary and the implications for our society and planet.”

Jim Powell, a geologist and Executive Director of the National Physical Science Consortium, was among the white-coated protesters. “I hope that the people who see the pictures and videos of the march will realize there’s a tremendous number of people who are not going to take it, and who are not going to standby while other people destroy the planet.”